Uma Oya Mega Project Showcasing the Skills of Iranian Engineering in Sri Lanka

Uma Oya Hydropower Complex

The CEO of a major Iranian contractor company involved in the construction of a hydropower project in Sri Lanka says works on the massive project has completely finished as he recounts how engineers from around the world were outsmarted by their Iranian rivals every step on the way.

Nasser Tarkeshdouz, who heads the Mahab Qods, the company that offered consultancy services in Uma Oya Multipurpose Development Project, said that this project would be seen as a representation of the potentials of a new generation of Iranian engineers.

“Iran had won this project in competition with powerful American, European and Asian companies,” said Tarkeshdouz of the project which will provide irrigation and drinking water to Badulla, Moneragala and Hambantota districts in southern Sri Lanka.

Iranian company Farab has executed the highly-complicated project which includes two dams with 35 and 50 meters of heights, a 15.5-kilometer-long irrigation tunnel and a 630-meter shaft which transfers water to a power plant that has a capacity of producing 120 megawatts of electricity.

Tarkeshdouz told the media that the shaft, fully designed and constructed by the Iranian engineers, should be viewed as a unique structure of its type in the world.

He said the Mahab Qods and Farab took over in Uma Oya after major international firms, including a famous Swiss engineering company, pulled out of the project due to various geographical and technical challenges.

“Sri Lanka needs water transfer for its very economic being but its ground and soil condition is one that causes subsidence and leak of water,” said Tarkeshdouz, adding, “Excavation operation in this country is not a job for everyone.”

He said drilling the main tunnel in the project was a heavy task that Iranian engineers managed to perform despite various problems that emerged.

“All problems in the project were solved through the strong and innovative hand of the Iranian engineers and now we witness ... the farms in this region are being saturated with water,” said Tarkeshdouz.

Iranian companies offering technical and engineering services have already found their way into major regional and international markets mainly thanks to government efforts to diversify the economy from oil and use exports of such services as a major source of foreign currency income at the time of increased American sanctions.

1-    Project Background

Uma Oya Multipurpose Development Project was officially commenced in Mach 2010 and the initial cost of 514 million US Dollars. However, due to the delays imposed on the Project for reasons which do not attributable to the Contractor, the Employer granted extension of Time for Completion of the Project. The Project is expected to be completed in this year.

2-    Objectives and Elements of the Project

Objectives of the Project is to transfer excess water, without affecting the downstream requirement, from upper reaches of Uma Oya basin to Kirindy Oya basin in the South-East Dry Zone, so that the demand for water in the region is met in an optimal manner. During this process, generation of optimal amount of hydropower is also considered as a requirement since there is a considerable difference in elevation between the locations of the sources of water and the area of demand, which can be effectively utilized for generation of hydropower.

This undated photo shows a worker on a tunnel boring machine operating inside a irrigation tunnel being constructed by the Iranian Farab company in Sri Lanka.

Required water is provided by storing behind the first dam (Puhulpola dam) which is a roller compacted concrete gravity type (RCC) and it is located on the Uma Oya River with 35 m height and gross storage of 634,826 m3. Then, the water be linked and conveyed through an approximately 3.75 km tunnel (D~4.6m) into the reservoir of another dam which has been built on Mahatotilla Oya River at Dyraaba location with 50 m height and gross storage of 970,135 m3 from where, another tunnel with approximate length of 15.5 km (D ~ 3.6m) with 618 m vertical shaft (D~2.2m) would convey water to the under-ground powerhouse. Outflow from the powerhouse will be directed into Alikota Ara which is a tributary of Kirindi River through an approximately 3.6 km (D~3.6m) Tailrace tunnel.

Randeniya switch yard is located at top of the powerhouse with 132 kv nominal voltage. The 23 kilometer double circuit 132 kV transmission line will connect the Uma Oya switch yard to Badula switch yard. This transmission line includes more than 85 towers.

The Uma Oya Multipurpose Development Project (UOMDP) will enable the diversion of 145 MCM of water from Uma Oya to Kirindi Oya through a 23 km-tunnel to be utilized for irrigation of 5,000 hectares of new lands in the South East Dry Zone of Sri Lanka and construct a hydro-electric plant to generate around 120 MW of electricity to the national grid to benefit all Sri Lankans.

Uma Oya Multipurpose Development Project includes the Puhulpola RCC Dam on the Uma Oya River, Dyraaba RCC Dam on Mahatotilla Oya River, a link tunnel from Puhulpola reservoir to Dyraaba reservoir, a headrace tunnel from Dyraaba Reservoir toward powerhouse, a vertical pressure shaft with steel lining, a surge tank on upstream of the vertical shaft, an underground powerhouse and its tailrace tunnel, Randeniya switchyard,23 km transmission line and Badulla switchyard .

3-    Current Progress

It is worth to mention that the elements of the Project are spread in vast area and far from each other, therefore, most well-known consulting engineers from Europe and Iran were employed for investigation, study and supervision. The final study was approved by the Employer. For the executions of the project, subcontractors from Iran, Sri Lanka and Europe have been in the job site and engaged in the different work fronts with engineers, technicians and labors from Sri Lanka, Iran and other countries. At the present 96.35% of the Project has been completed.

4-    A very short list of the positive impacts is given below:

·        Addition of 120 MW of power to the national grid which generates hydropower around 231 Gwh per year; equivalent to about 5% of the existing capacity. A major step forward in the path of progress of the country which itself will improve the living standards of many people and help the industrial and economic development.

·        Major changes in the agricultural activities in the South East Dry Zone, specifically the Hambantota, Monaragala, Ampara, and the neighboring districts. This will lead to an increase in food production and alleviate unemployment in the country to a very good extent.

·        Better management of water resources with the two dams in the project. This can help to reserve water supplies for dry seasons and also make use of flood waters to the benefit of general public.

·        Provide industrial and drinking water to Bandarawela, Hambantota harbor and Mattala airport to further help of the development of the region.

·        General improvement of life quality and a meaningful increase in the GSP (Gross State Product) and GNP of the country.